The end of summer and beginning of colder weather reminds us that nothing stays put forever - especially not fasteners. Colder weather brings the challenge of fluctuating temperatures, leading materials to contract and, in turn, fasteners to loosen. Left unchecked, this can spiral into equipment malfunctions, safety risks, and an uptick in maintenance costs, not to mention the headache of warranty and liability claims.
Thread locking serves as a critical countermeasure. It secures threaded fasteners such as bolts and screws, safeguarding them from the loosening effects of vibrations, temperature changes, and other operational stresses.
Understanding Thread Locking
The process of thread locking is exactly what it sounds like: It involves applying a specialized adhesive or mechanical device to the threads of a fastener. Thread lock adhesives solidify in the absence of air and create a bond with metal, filling gaps to prevent loosening and corrosion by stopping moisture and other corrosive elements from entering. This process ensures a reliable and more durable hold, reducing the risk of fastener failure.
Thread locking is particularly critical in applications where joint integrity is crucial, such as medical devices, the automotive and aerospace industries, military and defense, among others. And it can be tailored to take into account factors such as environmental conditions and the forces that the joint will encounter.
Choosing Thread Locking Techniques
Selecting the appropriate thread locking technique depends on the required holding strength, the environmental conditions expected, and the compatibility with specific metal types.
Here are a couple examples of each:
Chemical Thread Lockers
Anaerobic Adhesives: These most common chemical thread lockers work by curing in the absence of air and in the presence of metal ions.
Cyanoacrylate Adhesives: Known for their strength, this adhesive is most suitable for securing small screws.
Epoxy Resins: This two-part system is ideal for permanent thread locking applications.
Mechanical Thread Lockers
Nylon Inserts (Nyloc Nuts): These are nuts with a nylon collar insert that locks into the threads of a bolt, providing resistance to vibration.
Threaded Inserts (Helical Inserts or Heli-Coils): Metal coil inserts that provide a more durable thread in materials that may be too soft or prone to stripping.
Deformed Threads: Fasteners that have a deliberate deformation in the threads which creates interference in the threads when installed, providing locking action.
The bottom line: Thread locking is an essential step to ensure the longevity and integrity of fastened joints. It does this by preventing loosening due to vibration, shock or fluctuating environmental temperatures.
Choosing the best thread lock type adhesive takes know-how. A number of factors should be taken into account before making a final decision. Avoid problems by working with a professional.
For additional information, check out:
- Choosing and Using Thread Lock Adhesives
- What Threadlock Adhesive Are and How You Should Use Them
- What Are the Different Locking Fasteners Available?
Started my career in the fastener world in 1969 at, Parker Kalon Corp. a NJ based screw manufacturer located in Clifton, NJ working in inventory control, scheduling secondary production and concluding there in purchasing. In 1971 I accepted a sales position at Star Stainless Screw Co., Totowa, NJ working in inside sales and later as an outside salesman, having a successful career at Star I had the desire with a friend to start our own fastener distribution company in 1980 named: Divspec, Kenilworth, NJ. This was a successful adventure but ended in 1985 with me starting Melfast in August 1985 and have stayed competitive and successful to date. Melfast serves the OEM market with approximately 400 accounts nationally.